1. Field of the Invention
The present invention relates to a nozzle device and a handheld portion for a mini pump. In particular, the nozzle device and the handheld portion are made of two kinds of materials with different hardnesses.
2. Description of the Related Art
The nozzle device for a conventional mini pump 1 is provided for inflating a bicycle tire. Referring to FIG. 10, when holding the mini pump, a user's hand might sweat. The anti-sliding portion of the nozzle device and the holding portion of the mini pump where the user holds are usually adapted to prevent the mini pump sliding on the user's hand. The conventional anti-sliding portion and the holding portion of the mini pump are usually made from bicolor resins with different hardnesses. Specifically, the anti-sliding portion that is gripped by the user's finger is preferred to be softer resin than the holding portion that is held by the user's palm so that it is comfortable for the user to operate the pump. In addition, the bicolor resin is formed by a bi-color injection molding machine. Moreover, the nozzle device of the mini pump has interior threads for engaging with the head of the mini pump, and the holding portion of the head of the mini pump also has interior threads for engaging with the tube of the mini pump. However, the bi-color injection molding machine is driven via a rotary drive. If the step of forming the threads on parts of the mini pump has to be proceeded with the step of simultaneous bi-color injection molding the resin parts of the mini pump extra power is added to the rotary drive of the bi-color injection molding machine for multiple functions. Hence, the manufacture process will become extremely complicated, and the cost will increase.
The present invention is therefore intended to obviate or at least alleviate the problems encountered in the prior art.